In many ways, Darren Osborne was a template terrorist: a history of violence, drugs and alcohol abuse.
A former convict who had served a two-year sentence for assault. This is a typical CV for violent extremists.
But perhaps the most frightening aspect of his process of radicalisation was its pace.
It took just a few weeks - perhaps three of four - for Darren Osborne to turn into a murderous extremist.
In police interviews, his friends and relatives said he had never shared racist views with them before then.
The trigger, say investigators, was the acclaimed BBC drama ‘Three Girls’, based on the true stories of victims of the Rochdale grooming scandal. The subject matter became his obsession.
Osborne turned into a “ticking time bomb” making comments about “all Muslims raping children and being capable of blowing people up”. His former partner said he had become “brainwashed”.
Referring to him as “a devious, vile and hate-filled individual”, Metropolitan Police Commander Dean Haydon said Osborne’s rapid radicalisation process was among the briefest he had ever investigated.
But Osborne is not unique.
The shortening length of the path towards extremism is one of the defining trends of modern terrorism.
Brusthom Ziamani, the 19-year-old jihadist who was jailed in 2015 for plotting to behead a soldier with a 12-inch knife, and Mohamed Lahouaiej-Bouhlel, the lorry attacker who killed 86 people in Nice, France, appear to have both been radicalised within a few weeks.
All three were ‘followers’ rather than ‘leaders’, who used the internet to confirm or accelerate their beliefs. Osborne’s “pathway to radicalisation was online and following some high-profile figures," said Commander Haydon, referring to Tommy Robinson, founder of the English Defence League, and Jayda Fransen, deputy leader of Britain First.
Even Osborne’s identification of the singer Lily Allen as an appropriate hate figure reflects an online narrative on the extreme right wing.
Internet propaganda, more than anything else, is what’s abbreviating the radicalisation process. No longer is a real-world Anjem Choudary ‘leader’ required - to charm, to cajole and finally to convince the ‘follower’.
We cannot blame the BBC drama for triggering his hatred, which five million other people watched without a violent response.
To become a violent extremist is a choice.
But the toxic background noise of the internet is so often an accelerant.